John Andrews, 67, stuck a broom between his legs and galloped around the grounds of the Virginia Theological Seminary on Saturday. On any other day, it’s the sort of thing that might get a guy locked up.

But Andrews fit right in alongside the other keepers, chasers, bludgers and seekers trying their hand at an unusual but increasingly popular sport called quidditch.

Less than a decade old, the sport grew out of the Harry Potter novels. In the books, wizards and witches fly around on brooms tossing balls through elevated ring hoops — three on each side — while seekers search for the golden snitch.

In the real-life adaptation over the weekend, the hoops were Hula-Hoops mounted atop track hurdles. The snitch was a fleet-footed seminarian. The brooms were real, though they didn’t fly, of course.

While the sport got its start on college campuses, it’s growing fast. On the same day that the Virginia Theological Seminary hosted the free event, the Quidditch World Cup was underway in Florida. There’s even an International Quidditch Association, which counts teams in 45 states and five countries among its members.

Eight teams with seven players each competed in Alexandria. With games lasting just 12 minutes, the entire tournament took only about two hours. Officials were easy to spot: They wore big, black top hats. And at least one person was dressed in a full wizard garb.

The mix of top hats and broom-riding people of all ages on the normally quiet theological campus made more than a few joggers pause during their morning runs along Seminary Road. Several stopped for a closer look.

To the uninitiated, it must have seemed a little bizarre. But organizers said there was a higher purpose.

“It can be difficult to have intergenerational fun,” said Patricia Lyons, a teacher at St. Stephen’s and St. Agnes School who helped plan the event with the seminary.

The school hosted the tournament along with a free rock concert on the same day.

“It just gets hard for families, for churches, for sports leagues to provide opportunities where people can genuinely play together, and the truth is we’d probably do a lot of other things together — talk, grow, learn — if we could just competed together,” Lyons said.

During one game, Andrews and his friends, who were mostly in their 60s, played against a team with players in the second grade.

“It was great after going to all of the movies to go out and play,” said Andrews, who drove up from the Hampton area. “As far as sportsmanship, it’s all just fun. It isn’t about how do you go and beat them up. No, you’re just out there having a good time.”

Perhaps the youngest player on the field was Matthew Haynes, a second grader at Matthew Maury Elementary School in Alexandria. He played three positions throughout the day: keeper, beater and bludger.

Haynes had several impressive saves, swatting away balls with his broom as opposing teams tried to throw them into the three hoops that he was guarding. Still, he said bludger was his favorite position.

“You throw balls at people,” he said, explaining the appeal.

The championship paired St. Stephen’s and St. Agnes School with a youth group from Easton, Md. Capturing the snitch meant 150 points, an instant win, while tossing the ball through a hoop was good for 15 points.

The seeker on each team had to grab what looked like a towel hanging from the snitch’s back pocket to capture him. The snitch was not restricted to the field of play. And from the looks of things, he seemed to be a pretty accomplished distance runner. He sprinted up a hill, disappearing off on the other side of the sprawling seminary campus. Soon, he was gone.

The two seekers awkwardly galloped off after the snitch holding brooms between their legs. Neither appeared to have much of a chance. So it seemed almost certain, then, that the game would come down to the team that had the most shots through the hoops.

With time running out, St. Stephens was clearly winning in that department. But just when it looked like the local school would win it all, things changed with the snap of the fingers.

“I got him!” one of the Easton players yelled from afar with about a minute left to play.

The winning seeker, Dean O’Donnell, 19, took a few minutes after catching his breath to recount how it happened. After all, nobody on the field could see a thing.

“We took off toward the buildings and the other seeker was in front of me, so mostly I was following him the whole time to see where he was,” he said. “Then I saw the other seeker look kind of lost, so he obviously lost the snitch. So I scoured the buildings and I got near the concert stage, and then out of the corner of my eye, I saw him running. … I went full speed for him and I had to chase him for a while.